Sending another 10% for A/B testing after I already sent 10%

I am doing an A/B test and have already sent out the original 10% for testing. Now we want to send out another 10% before declaring a winner. Can this be done or or should I just abandon this program, start over w/a new one and do another a/b testing after I remove the 10% that got sent originally?  Is there a simpler way to send another 10% w/o having to start over?